use raster attributes width/height

src/jexer/tterminal/DisplayLine.java

@@ -91,7 +91,7 @@ public class DisplayLine {
         for (Cell cell: line.chars) {
             chars.add(new Cell(cell));
         }
-        attr = line.attr;
+        attr = new CellAttributes(line.attr);
         doubleWidth = line.doubleWidth;
         doubleHeight = line.doubleHeight;
         reverseColor = line.reverseColor;
@@ -103,7 +103,7 @@ public class DisplayLine {
      * @param attr current drawing attributes
      */
     public DisplayLine(final CellAttributes attr) {
-        this.attr = attr;
+        this.attr = new CellAttributes(attr);
     }
 
     // ------------------------------------------------------------------------

src/jexer/tterminal/ECMA48.java

@@ -5267,7 +5267,9 @@ public class ECMA48 implements Runnable {
         switch (item) {
         case 1:
             if (action == 1) {
-                // Report number of color registers.
+                // Report number of color registers.  Though we can support
+                // effectively unlimited colors, report the same max as stock
+                // xterm (MAX_COLOR_REGISTERS).
                 writeRemote(String.format("\033[?%d;%d;%dS", item, 0, 1024));
                 return;
             }

src/jexer/tterminal/Sixel.java

@@ -204,6 +204,8 @@ public class Sixel {
             if ((rasterWidth > width) || (rasterHeight > y + 1)) {
                 resizeImage(Math.max(width, rasterWidth),
                     Math.max(y + 1, rasterHeight));
+                return image.getSubimage(0, 0, Math.max(width, rasterWidth),
+                    Math.max(y + 1, rasterHeight));
             }
             return image.getSubimage(0, 0, width, y + 1);
         }